Is it permissible for a veiled Muslim woman to be a godmother to a Christian child and to enter the church to attend her baptism ceremony?

The basic ruling for entering a church is permissibility. However, taking one's daughter to a priest for him to bless her is not permissible, because it involves an affirmation of, and assistance with, false beliefs and rituals, and seeking blessings from someone who has no blessings to give.